They're not going to just roll over for Microsoft. The folks in Redmond will have to WORK to claim that coveted "3rd Ecosystem" title. BlackBerry is looking at BB10 much the same way Nokia looked at WP8 - a whole new beginning and a chance at redemption.
NOK has a proven product lumia 920 with a proven win8. Let us wait and see when BB10 comes out and then we will talk. May be all nok needs is a bb gun to shoot rimm and finish it off and may not ven need a shotgun, lol.